Translational neuroimaging in mild traumatic brain injury.

Traumatic brain injuries (TBIs) are common with an estimated 27.1 million cases per year. Approximately 80% of TBIs are categorized as mild TBI (mTBI) based on initial symptom presentation. While in most individuals, symptoms resolve within days to weeks, in some, symptoms become chronic. Advanced neuroimaging has the potential to characterize brain morphometric, microstructural, biochemical, and metabolic abnormalities following mTBI. However, translational studies are needed for the interpretation of neuroimaging findings in humans with respect to the underlying pathophysiological processes, and, ultimately, for developing novel and more targeted treatment options. In this review, we introduce the most commonly used animal models for the study of mTBI. We then summarize the neuroimaging findings in humans and animals after mTBI and, wherever applicable, the translational aspects of studies available today. Finally, we highlight the importance of translational approaches and outline future perspectives in the field of translational neuroimaging in mTBI.

Sonic hedgehog expression in zebrafish forebrain identifies the teleostean pallidal signaling center and shows preglomerular complex and posterior tubercular dopamine cells to arise from shh cells.

Ventralization, a major patterning process in the developing vertebrate neural tube (central nervous system, CNS), depends on Sonic hedgehog (SHH) as a main signaling morphogen. We studied the CNS of late larval and young adult zebrafish in a transgenic shh-GFP line revealing increased neuroanatomical detail due to the progressed differentiation state compared to earlier stages. Some major findings emerge from the present study. (a) shh -GFP is still expressed along the adult zebrafish CNS neuraxis in most locations seen in larvae. (b) We newly identify a ventroposterior shh pallidal domain representing the basal telencephalic signaling center important for basal ganglia development known in other vertebrates (i.e., the anterior entopeduncular area-basal medial ganglionic eminence of mammals). (c) We further show late-emerging shh-GFP positive radial glia cells in the medial zone of the dorsal telencephalon (i.e., the teleostan pallial amygdala). (d) Immunostains for tyrosine hydroxylase demonstrate that there is selective colocalization in adult dopamine cells with shh-GFP in the posterior tuberculum, including in projection cells to striatum, which represents a striking parallel to amniote mesodiencephalic dopamine cell origin from shh expressing floor plate cells. (e) There is no colocalization of shh and islet1 as shown by respective shh-GFP and islet1-GFP lines. (f) The only radially far migrated shh-GFP cells are located in the preglomerular area. (g) There are no adult cerebellar and tectal shh-GFP cells confirming their exclusive role during early development as previously reported by our laboratory.

Relationship between body mass index and knee alignment using non-radiographic / umbilical method.

Aim: The aim of the research was to investigate the relationship between body mass index and knee alignment angle using non-radiographic methods, and to propose a regression equation to define the relationship.Method: A total of 300 students (200 males, 100 females) of Nnamdi Azikiwe University, Nnewi campus participated in the study. Knee alignment was measured using body landmarks (umbilicus, right knee and right second toe) with a goniometer and calliper; the body mass index was also determined.Result: The male subjects had a mean body mass index of 24.2 kg/m2 and knee alignment angle of 176.5o. The female participants had a mean body mass index of 22.7 kg/m2 and knee alignment angle of 180.9o. Body mass index had no significant relationship with knee alignment in both males and females respectively (r = 0.009, p > 0.05; r = 0.065, p > 0.05). Conclusion: The study showed no significant positive relationship between body mass index and knee alignment, and body mass index is therefore not a good determinant for the control of knee alignment-based knee osteoarthritis.